Production of drawing-pins, wiretacks, and the like



May E2, 1936. J. HOCKEiLMANN v 2,@4,53

PRODUCTION OF DRAWING PINS, WIRE TACKS AND THE LIKE Filed April '25, 1932 2 Sheets-Sheet 1 In vebiorz J. HOCKELMANN 2,040,553

PRODUCTION OF "DRAWING PINS, WIRE TAC KS AND THE LIKE Filed April 23, 1952 2 Sheets-Sheet 2- F133 lllllll Fig.2

/ In V022 for W Patented May 12, 1936 UNITED STATES PATENT OFFICE PRODUCTION OF DRAWING-PINS, WIRE- TACKS, AND THE LIKE Application April 23, 1932, Serial No. 607,188 In Germany April 29, 1931 12 Claims.

This invention relates to the production of drawing pins, wire tacks and the like, having heads preferably of disk like proportions which may be conveyed from a pin forming machine or 5 other source to means for sharpening or grinding points thereon by which the said devices can be easily embedded in a base or other element. Since the uses to which pins of this kind are susceptible are so numerous, it is unnecessary to enlarge upon a description in that regard.

With the foregoing in View, the invention consists in the details of construction and in the arrangement and combination of parts to be hereinafter more fully set forth and claimed.

In describing the invention in detail, reference will be had to the accompanying drawings forming part of this application wherein like characters denote corresponding parts in the several views, and in which- Fig. 1 shows a machine for grinding the point of the drawing-board pin in lateral view and partly in vertical section.

Fig. 2 is a lateral view, partly in vertical section, displaced from Fig. 1 by 90.

25 Fig. 3 is a plan view of the plate of the machine holding the pins to be ground.

The aforesaid drawing pins may be fed to a grinding device such as is illustrated in Figures 1 to 3 inclusive. This device is provided upon a horizontal, constantly revolving shaft 23 with a grind-stone 22 one side face of which serves as a working surface and is shaped slightly conical corresponding to the conical shape to be imparted to the points of the nails or pins. In other words, the side surface of the grinding element which in reality may be termed a grinding disk is the effective grinding portion of the element when the pins are brought into grinding position with relation to it, so that hereafter grinding wheel or disk may be used alternatively. Above this grind-stone or wheel a fixed horizontal plate 4, capable of being raised or lowered, has been arranged, being provided with a longitudinal slot 5, one end of which is coincident with the conical working surface of the stone 22. A feeding channel or groove 24 for the pins to be ground, e. g. drawing pins opens into the slot 5 of the plate 4, said feeding channel or groove being connected with a known container. In connection herewith the mouth of the channel or groove is so disposed, that the nail or pin leaving the channel or groove 24 at the time, enters with its pin or shank into the slot of the plate 4, whilst the head-plate c of the hall or pin establishes contact with the upper surface of the holding plate 4. The drawingboard pins are held fast in the feeding channel or groove 24 by means of a spring I4. At regular intervals an elastic finger l5 presses the lowermost nail, being in that position at the time, 5 in the channel or groove, past the springs I4 with the result that it is free to slip to the mouth of the channel or groove and thence on or into the holding-plate 4. A feed-organ I6 projects into the slot 5 of the plate 4 to push the pin, the 10 Y point of which lies in the slot to the right end of the slot, thus placing it into the position required for grinding the point. The feed organ I6 is formed by the angular arm of a doublearmed lever H, the other arm of which is coupled 15 to a second double-armed lever l9 by means of a connecting rod l8. This lever is made to carry a roller not shown in the drawing which so cooperates with a cam-disk 20, that the arm I6 is swung to the right at regular intervals for the 20 purpose of feeding forward a drawing-pin (Fig. 1). The levers l1 and I9 return each time after the feed of the drawing-pin into their original position under the action of a spring 2|. The elastic finger l5 and the cam-disk 20 are carried 25 by a shaft '6, also constantly revolving, being disposed horizontally above the plate.

This shaft 6 carries in addition thereto a friction disk or wheel I which is so disposed, that it touches with its face the head-plate of the drawing pin 0 which is at the end of the slot 5 at the time. In connection herewith the disk I occupies a tangential position to the head-plate, so that it is adapted to revolve the nail or pin in the slot 5. The disk 1 has the shape of a sector, the arc of which measures almost 180, so that it is actuated each time during half a rotation of the shaft 6, whilst it remains out of action during the other half of the rotation of the shaft.

At the under-side of the holding-plate 4 a double-armed lever 8, 3 is provided, the ends of which, bent upwardly, are guided in holes of the holding-plate 4, said lever being ordinarily held in a position of rest by a spring H] as shown in Fig. 1. The end of the one lever-arm 8 is situated below the head-plate of the drawing-pin being at the end of the slot 5 at the time where it establishes contact with the upper surface of the plate 4, when the lever is in a position of rest. The end of the other lever-arm 9 projects through the plate 4 in an upward direction, being situated within reach of an arm I I carried by the shaft 6. This arm serves, on the one hand, to so turn the lever B, 9 by exercising pressure on the lever-arm 9 by means of its free end suitably provided with a contact-surface, that the lever-arm 8 lifts the nail or pin at the right end of the slot 5 and ejects it therefrom, i. e. from the position in which its point is being ground. The arm I I is so arranged in relation to the sector-shaped friction disk 1, that the lever B, 9 becomes operative as soon as the face l2 of the friction disk is lifted off the head of the drawing-pin. Furthermore, the cam-disk 20 is so disposed, that the feed-organ becomes operative after the actuation of the levers 8, 9, so that each time, after a ground nail or pin has been removed, another nail or pin is fed to the arm IS.

The face of the friction disk 1 is provided with a comparatively thick layer I2 consisting of rubber or any other suitable elastic material which will render it possible to yieldingly press the drawing-pin against the grind-stone, causing the nail or pin, which is in the first instance placed slightly above the holding-plate B, to be gradually pressed down, thus being fed forward along its axial direction against the working surface of the grind-stone as required in the course of the grinding process;

The method of working of the grinding device is, briefly stated, as follows:

In the position of the parts as shown in Figs. 1 and 2 a drawing-pin is situated at the right end of the slide of the holdingeplate 4 and thus in the position of being ground or sharpened. The friction disk 1 turning in therdirection of the arrow it becomes now operative, so that the nail or pin is turned around its axis, simultaneously being pressed against the conical working surface of the grind-stone or wheel 22 in the direction of the axis of the nail or pin, whereby the point of the nail or pin will be ground or sharpened. As soon as the contact between the friction disk and the head-plate of the nail or pin is interrupted; the arm H turns the lever B, 9, causing the nail or pin which has been released by the friction-disk, to be'ejected. The arm It new places a fresh nail or pin into the slot 5 at the end thereof, causing said nail or pin to be placed in contact with the grindstone or wheel 22 thus repeating the modus operandi previously described.

I claim:

1. A device of the kind described including a grindingwheel, means to hold an unsharpened drawing-pin having a disk-like head in freely revoluble position with thepoint portion in contact with the grinding wheel, and revolving friction means engaging a flat face of the disk-like head of the pin at its peripheral portion when in grinding position whereby to rotate the pm as. it is ground, and means for rotatably mounting the grinding wheel with its side surface engaging the pin.

2. A device of the kind described including a grinding wheel, means to support a headed drawing-pin revolubly with its point in contact with the grinding wheeel, a revolving friction wheel engaging the peripheral portion of the pin head to cause rotation of the pin, said friction wheel having a portion of its periphery interrupted to form a gap, an ejecting device arranged to eject the pin from the supporting means, and means to effect operation of said ejecting device in timed relation to the friction wheel.

3. A device of the kind described including a grinding wheel, means to support a headed drawing-pin revolubly with its. point in contact with the grinding wheel, a revolving friction wheel engaging the peripheral portion of the pin head to cause rotation of the pin, said friction wheel having a portion of its periphery interrupted to form a gap, an ejecting device arranged to eject the pin from the supporting means, a shaft hav- 5 7 ing said friction wheel fixed thereon, and an arm fixed to the shaft and engaging and operating the ejecting device in timed relation to the operation of the friction wheel.

4. A device of the kind described including a 10 grinding wheel and means to rotate the same, a plate extending across the periphery of said grinding wheel and having a slot therein to receive the shank of a headed drawing-pin, said slot having an end terminating opposite the grinding wheel, said plate being sufficiently thin to permit the point portion of the pin shank to engage said grinding wheel, and friction means adjacent said end of the slot and positioned to engage the pin head when held in said slot to rotate the pin and press the head against said plate.

5. A device of the kind described including a grinding wheel and means to rotate the same, a plate extending across the periphery of sald'25 grinding wheel and having a slot therein to receive the shank of a headed drawing-pin, said slot having an end terminating opposite the grinding Wheel, said plate being sufiiciently thin to permit the point portion ofthe pin shank to engage said grinding wheel, and arevoluble friction disk extending transversely across the slot adjacent said end and engaging the pin head adjacent its periphery to rotate the pin and hold its head pressed on the plate.

6. A device of the kind described including a grinding wheel and means to rotate the same, a plate extending across the periphery of said grinding wheel and having a slot therein to receive the shank of a headed drawing-pin, said slot having an end terminating opposite the grinding wheel, said plate being sufficiently thin to permit the point portion of thepin shank to engage said grinding wheel, a revoluble friction disk extending transversely across the slot adjacent said end and engaging the pin head adjacent its periphery to rotate the pin and hold its head pressed on the plate, said disk having a portion of its periphery of less radius than the pin head engaging portion to form a gap wherein the pin head rides free, and an ejecting device operating to eject the pin from the slot when the gap is opposite said head.

'7. Ardevice of the kind described including a grinding wheel and means to rotate the same,; a

plate extending across the periphery or, said grinding wheel and having a slot therein to receive the shank of a headed drawing-pin, said slot having an end terminating opposite. the grinding wheel, said plate being sufficiently thin to permit the point portion of the pin shank to engage said 50 grinding wheel, a revoluble friction disk extending transversely across the slot adjacent said endand engaging the pin head adjacent its periphery to rotate the pin and hold its head pressed on the plate, said disk having a portion of its periphery of less radius than the pin head engaging portion to form a gap wherein the pin head rides free, a shaft whereon said friction disk is fixed, an ejecting device arranged to lift the pin from said slot, and means to operate said ejecting device upon the said gap being opposite the pin head.

8. A device of the kind described including, a grinding wheel and means to rotate the same, a plate extending across the periphery of said grinding wheel and having a slot therein to receive the shank of a headed drawing-pin, said slot having an end terminating opposite the grinding wheel, said plate being sufficiently thin to permit the point portion of the pin shank to engage said grinding wheel, a revoluble friction disk extending transversely across the slot adjacent said end and engaging the pin head adjacent its periphery to rotate the pin and hold its head pressed on the plate, said disk having a portion of its periphery of less radius than the pin head engaging portion to form a gap wherein the pin head rides free, a shaft whereon said friction disk is fixed, an ejecting device arranged to lift the pin from said slot, and an arm fixed on said shaft to engage and operate said ejecting device upon the said gap being opposite the pin head.

9. A device of the kind described including a grinding wheel and means to rotate the same, a plate extending across the periphery of said grinding wheel and having a slot therein to receive the shank of a headed drawing-pin, said slot having an end terminating opposite the grinding wheel, said plate being sufliciently thin to permit the point portion of the pin shank to engage said grinding wheel, a revoluble friction disk extending transversely across the slot adjacent said end and engaging the pin head adjacent its periphery to rotate the pin and hold its head pressed on the plate, said disk having a portion of its periphery of less radius than the pin head engaging portion to form a gap wherein the pin head rides free, an ejecting device operating to eject the pin from the slot when the gap is opposite said head, means to feed pins in succession into the end of the slot remote from the grinding wheel, and feeder means operating in timed relation to the operation of the friction disk and feeding the pins one by one along the slot to the end adjacent the grinding disk.

10. A device of the kind described including a grinding wheel and means to rotate the same, a plate extending across the periphery of said grinding wheel and having a slot therein to receive the shank of a headed drawing-pin, said slot having an end terminating opposite the grinding wheel, said plate being sufficiently thin to permit the point portion of the pin shank to engage said grinding wheel, a revoluble friction disk extending transversely across the slot adjacent said end and engaging the pin head adjacent its periphery to rotate the pin and hold its head pressed on the plate, said disk having a portion of its periphery of less radius than the pin head engaging portion to form a gap wherein the pin head rides free, a shaft whereon said friction disk is fixed, an ejecting device arranged to lift the pin from said slot, means to operate said ejecting device upon the said gap being opposite the pin head, means to feed pins in succession into the end of the slot remote from the grinding wheel, and feeder means operating in timed relation to the operation of the friction disk and feeding the pins one by one along the-slot to the end adjacent the grinding disk.

11. A device of the kind described including a grinding wheel and means to rotate the same, a

plate extending across the periphery of said grinding wheel and having a slot therein to receive the shank of a headed drawing-pin, said slot having an end terminating opposite the grinding wheel, said plate being sufliciently thin to permit the point portion of the pin shank to engage said grinding wheel, a revoluble friction disk extending transversely across the slot adjacent said end and engaging the pin head adjacent its periphery to rotate the pin and hold its head pressed on the plate, said disk having a portion of its periphery of less radius than the pin head engaging portion to form a gap wherein the pin head rides free, a shaft'whereon said friction disk is fixed, an ejecting device arranged to lift the pin from said slot, an arm fixed on said shaft to engage and operate said ejecting device upon the said gap being opposite the pin head, means to feed pins in succession into the end of the slot remote from the grinding wheel, and feeder means operating in timed relation to the operation of the friction disk and feeding the pins one by one along the slot to the end adjacent the grinding disk.

12. In a machine for grinding disk headed drafting pins, a grinding wheel, means to hold the unsharpened drawing pin having a disk-like head in freely revoluble position with the point portion of the pin in contact with the side face of the grinding wheel, and a revolubly driven element engaging the top face of the head of the pin laterally'of its center when in grinding position for rotating the pin as it is ground.

JiiLIiis HOCKELMANN. 

